Step ladders of various constructions have long been employed to allow workmen and others to reach elevated positions in and about factories, commercial buildings, homes and the like. The usual prior art ladders, of the type contemplated by the present invention, have most frequently been designed in three distinct styles, namely, an A-shaped folding step ladder, an I-shaped straight ladder, or an I-shaped, straight extension ladder. Certain prior designs have permitted two or more I-shaped ladder segments to be joined in end-to-end juxtaposition to create I-shaped combinations of increased length or reach. However, so far as is known to the applicant, there has never been a single design which could permit a single pair of straight ladder sections to optionally be arranged as an A-shaped step ladder, a single section straight ladder, or a double section elongated straight ladder.